Device for applying marks to photographic paper



'APl'il15y1969 R. LuEscH ER 3,438,354

DEVICE FOR APPLYING MARKS To PHOTOGRAPHIC PAPER Filed July 6, 1967 y I Sheet of 2 Fig.2

INVENTOR.

Rene Luescher I BY April 15, 1969 DBVICEFOR APPLYING MARKS TO FHOT-OGRAPHIC PAPER Filed July 6, 1967 s eet 3 -01" z Re HQ LU QS cher- 1 Ja g gewx 1M4,

R. LUE-SCHER 3,43

United States Patent U.S. Cl. 118-76 6 Claims ABSTRACT OF THE DISCLOSURE A marking device for applying marks to photographic paper comprising an epicyclic transmission, a reversible D.C. electric motor for driving the sun wheel, a planet wheel arm pivotable on the sun wheel shaft, a planet wheel shaft carried by the planet wheel arm, a marking wheel on the planet wheel shaft and a brake acting on one of the gear shafts. Rotation of the motor in one direction causes the planet wheel to climb around the sun wheel as a result of the brake, thus, bringing the marking wheel into contact with the paper. Rotation of the motor in the other direction lifts the marking wheel off the paper.

This invention relates to a marking device.

For cutting lengths of paper from rolls, particularly lengths of exposed and developed photographic paper according to the size of the printed pictures, it has been proposed to feed the paper through automatic cutting equipment in which the pictures are cut off by reference to marks previously applied to the paper. It is desirable to explore the paper for the marks by two electrodes which are electrically connected when they ride over the marks. A suitable marking material for such a purpose is for instance graphite. However, it is not easy to provide the photographic paper with electrically conducting mar-kings-which are sufficiently permanent not to be washed off when the paper is passed through a bath. It is an object of the invention to provide a marking device which will form permanent markings on material, particularly photographic paper.

According to the invention there is provided a marking device comprising an electric motor, rotatable in two directions, switch means for starting, reversing the direction of rotation and stopping the motor, an epicyclic transmission including a sun wheel mounted fast on a sun wheel shaft drivable by the motor, a planet wheel mounted fast on a planet wheel shaft and an intermediate gear mounted on an intermediate gear shaft, a marking wheel mounted fast on the planet wheel shaft and a planet wheel arm pivotably mounted on the sun wheel shaft, said planet wheel arm carrying said planet wheel shaft, and said intermediate gear shaft, friction brake means mounted on the planet wheel arm and actuable on one of the three shafts such that rotation of the motor in one direction causes one of the three shafts and hence the marking Wheel to be deflected in a first direction whereby the marking wheel is brought into contact with material to be marked and rotation of the motor in the other direction causes one of the three shafts and hence the marking wheel to be deflected in a second direction counter to the first direction whereby the marking wheel is brought out of contact with material to be marked.

The marking device according to the invention solves the problem of providing permanent marks on photographic paper because the rotating marking wheel is into the surface of the photographic paper, the contact Patented Apr. 15, 1969 ICC pressure being controllable by adjusting the friction of the brake.

In a preferred embodiment of the invention the motor is a DC. motor and the switch means includes a control unit to start the rotation of the motor and a relay having contacts for reversing the polarity of the current supplied to the motor to change the direction of rotation of the motor. Preferably, the switch means further includes a limit switch actuable to stop the motor when said marking wheel is brought out of contact with material to be marked by deflection in said second direction. The switch means required may be particularly simple in design since the polarity of the current supplied to the motor need merely be reversed for lifting the marking wheel off the paper.

Specific embodiments of the invention will now be described by way of example with reference to the accompanying drawings in which:

FIGURE 1 is a plan view of the proposed marking device,

FIGURE 2 is an elevational section of the marking device and its casing and a schematic representation of the associated electrical control circuitry,

FIGURE 3 is a cross section drawn to a larger scale,

FIGURES 4 to 6 represent working positions of the marking device and FIGURES 7 and 8 illustrate arrangements comprising eccentrics.

In the drawings a DC. motor 16 is secured at one end of a casing 11 which casing is slida'bly movable on two rails 12 of an adjusting means, not shown in the drawings, and locatable in any desired position by a clamping bar 13 and a nut 14 having a milled edge. Through a gear transmission comprising a worm 17 and a wormwheel 18 the motor 16 is adapted to drive a shaft 19 mounted in bearing bushes 20 in the casing 11. Shaft 19 is the centre shaft of an epicyclic transmission comprising a sun wheel 21 fast on shaft 19, a planet wheel 22 which meshes with an intermediate gear 23 driven by the sun wheel 21 and an arm 24 which is pivotable on the shaft 19 and which carries a shaft 25 and 26 for the intermediate gear 23 and the planet whweel 22 respectively. The planet wheel shaft 26 to which the planet wheel 22 is keyed has also a hub 27 keyed thereto. A marking wheel 29 is detachably aflixed to the hub 27 by means of a nut 28 having a milled edge. The marking wheel is preferably made of graphite but may however consist of some other electrically conducting material that can be abraded, such as silver. Built into the arm 24 is a friction brake which co-operates with the planet wheel shaft 26. The friction brake comprises a brake shoe 31 which is contained in a bore extending radially towards the shaft 26, and which is urged by a spring 32 into contact with the shaft 26, generating friction when the shaft rotates. In the position of rest the arm 24 bears against a fixed stop 33 thereby holding a limit switch 34 in the casing 11 in the open position.

Switch means for controlling the motor are connected to a DC. source and comprise a relay 35 with pole-reversing change-over contacts 36, 37, a control unit 39 and the limit switch 34. Four diodes forming a conventional rectifier bridge 38 are interposed between the DC. source and the motor windings to suppress sparking. The switch means are illustrated in position of rest.

When the coil of the relay 35 is connected for instance by closing a switch in the control unit 39 to the positive pole of the DC. source the contacts 36 and 37 change over and co-operate with working contacts a, causing the motor to run in the forward direction, say anticlockwise. This rotation of the motor causes the arm 24 to be tilted towards a piece of paper 40 that is to be marked, as indicated by an arrow 41 in FIGURE 4, into the working position illustrated in FIGURE 5 in which the marking wheel 29 applies pressure to the paper and produces a mark by rubbing at is revolves in the arrowed direction. In the position shown in FIGURE 5, the limit switch 34, which is contained in the circuit for reverse rotation, is closed. When the coil 35 of the relay is deenergized by opening the switch in the control unit the relay contacts 36 and 37 change back and co-operate with the resting contacts r; reversing the polarity of the current driving the motor and the motor begins to rotate backwards, that is clockwise, as indicated in FIGURE 6. Consequently the arm 24 moves back into its position of rest in the direction of arrow 4-2 until engaged by the stop 33, simultaneously opening the limit switch 34 and stopping the motor.

Since only a very small surface area of the marking wheel actually makes contact with the paper during the marking period the resultant mark is a small line, the length of the line being equal to the width of the marking wheel 29. The width of the line can be increased by imparting in addition to therevolving of the marking wheel a slight reciprocating movement to the marking wheel in a direction substantially parallel to the plane of the paper.

In the embodiment shown in FIGURE 7, a part of the shaft 19 is an eccentric shaft 50 with an eccentricity e. The sun wheel 21 is fastened on the eccentric shaft 50 and the arm 24 is pivotable on said eccentric shaft. The simplified epicyclic transmission comprises the sun wheel 21 and the planet wheel 22. The marking wheel 29 is aflixed on the planet wheel shaft 26.

In the embodiment according to FIGURE 8 the simplified epicyclic transmission comprises the sun wheel 21 fastened on the shaft 19 and the planet wheel 22 keyed on the planet wheel shaft 26. The marking wheel 29 is mounted with eccentricity e on the planet wheel shaft 26. In both of these last two embodiments the eccentricity 2 produces a reciprocating movement of the marking wheel of magnitude 2e which then determines the width of the line marked on the paper.

I claim:

1. A marking device comprising (a) an electric motor, rotatable in two directions,

(b) switch means for starting, reversing the direction of rotation and stopping the motor,

- (c) an epicyclic transmission including a sun wheel mounted fast on a sun wheel shaft drivable by the motor, a planet wheel mounted fast on a planet wheel shaft, and an intermediated gear mounted on the intermediate gear shaft,

(d) a marking wheel mounted fast on the planet wheel shaft and,

(e) a planet wheel arm pivotably mounted on the sun wheel shaft, said planet wheel arm carrying said planet wheel shaft and said intermediate gear shaft,

(f) friction brake means mounted on the planet wheel arm and actuable on one of the three shafts such that rotation of the motor in one direction causes one of the three shafts and hence the marking wheel to be deflected in a first direction whereby the marking wheel is brought into contact with material to be marked and rotation of the motor in the other direction causes one of the three shafts and hence the marking wheel to be deflected in a second direction counter to the first direction whereby the marking wheel is brought out of contact with material to be marked.

2. The marking device of claim 1, wherein the friction brake means includes means defining a bore in said planet wheel arm extending to one of said shafts, a brake shoe in said bore adjacent one of the shafts and spring means in said bore for urging the brake shoe towards one of the shafts.

3. The marking device of claim 1, wherein the electric motor is a DC. motor, said switch means including a control unit to start the rotation of the motor in said first direction, said switch means further comprising relay means including contacts for reversing the direction of rotation of the motor, said switch means further including a limit switch actuable to stop the motor when said mark- "ing wheel is brought out of contact with material to be marked by deflection in said second direction.

4. The marking device of claim 3 wherein the epicyclic transmission includes an eccentric for imparting reciprocating movement to the marking wheel in a direction substantially parallel to the plane of the material to be marked.

'5. The marking device of claim 4, wherein the marking wheel is eccentrically mounted on the planet wheel shaft.

6. The marking device of claim 4, wherein a part of the sun wheel shaft is an eccentric shaft and the planet wheel arm and the sun wheel are mounted on the eccentric shaft.

References Cited UNITED STATES PATENTS 3,029,773 4/1962 Collins 118-241 XR 3,367,301 2/ 1968 Foley et al 118--241XR ROBERT W. MICHELL, Primary Examiner. -R. I. SMITH, Assistant Examiner. I

US. Cl. X.R. 

